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Adhemaz Noercahya Putranto 2020710450217 TUGAS TERMODINAMIKA 10 April 2021
1. Calculate the reversible work done in compressing 0.0283 m3 of mercury at a constant temperature of 273.15 K(O°C) from 1 atm to 3000 atm. The isothermal compressibility of mercury at 273.15 K(O"C) is where P is in atm and K is in atm-'.
2. Calculate Z and V for ethylene at 298.15 K (25°C) and 12 bar by the following equations: (a) The truncated virial equation [Eq. (3.39)] with the following experimental values of virial coefficients: (b) The truncated virial equation [Eq. (3.37)], with a value of B from the generalized Pitzer correlation [Eq. (3.59)]. (c) The RedlicWKwong equation. (d) The Soave/Redlich/Kwong equation. (e) The PengJRobinson equation.
3. Calculate the molar volume of saturated liquid and the molar volume of saturated vapor by the RedlichIKwong equation for one of the following and compare results with values found by suitable generalized correlations. (a) Propane at 313.15 K(40°C) where PSat = 13.71 bar. (b) Propane at 323.15 K(50°C) where PSat = 17.16 bar. (c) n-Butane at 373.15 K(100oC) where PSat = 15.41 bar.
Jawaban
a. Dik : v = 0,0283 m3 = 1 ft3 T = 273,15 K P1 = 1 atm P2 = 3000 atm
κ = 3,9 x 10-6 – 0,1 x 10-9 Reversible work for closed system define as ❑
W =−∫ PdV ❑
From isothermal compressibility k
k=
−1 dV T v dP
( )
Kita dapatkan
dV =−V kdP Lalu substitusikan dV dan W P2
W =V ∫ ( Vk ) dP P1 P2
W =V ∫ ( a−bP ) PdP P1
a b W =V ( P 2−P 1 )− (P2−P1) 2 3
[
❑
]
3,9 x 10−6 0,1 x 10−9 ( ) ( 30002−12) W =1 3000−1 − 2 3
[
W =16,65 ft 3 . atm
b.
Dik :
T = 298,15 K P = 12 bar Tc = 282,3 K Pc = 50,6 bar B = 140 cm3/mol C = 7200 cm6/mol R = 83,14 cm3 bar/mol K Tr = 1,056 K Pr = 0,2731 bar
a.
Z=
PV B C =1− − 2 RT V V
❑
]
RT −B P 83,14.298,15 V= −140 12 V =1926 cm3/mol V=
Iterasi RT B C V 1= (1− + 2 ) P Vo Vo 83,14.289,15 140 7200 V 1= (1− + ) 12 1926 19262 V 1=1919,834 140 7200 V 2=2066 1− + 1919,834 1919,834 2 V 2=1919,377
(
)
Setelah iterasi ke 5 diperoleh hasil V = 1919,34 cm3/mol Z = 0,8631
b.
Z=1+Bo
Pr Pr +ω B 1 Tr Tr
0,422 Tr 1,6 0,422 Bo=0,083− 1,056 1,6 Bo=−0,304 Bo=0,083−
0,172 Tr 4,2 B1=2,262 x 10−3 B1=0,139−
ω=0,089
Substitusikan ke persamaan Z Z=1+(−0,304) Z=0,9254 V=
ZRT P
0,2731 +¿ 1,056
0,9254.83,14 .298,15 12 V =1911,70028 cm3 /mol V=
c. Redlich/Kwong Equation Untuk persamaan RK: σεαΨβωΩ σ
=1
ε
=0
Ψ
= 0,42748
Ω
= 0,08664
α
= Tr-0,5 = 0,973124
q
=
β
=Ω
Z
= 1+ β−q β
Ψ .α Ω .Tr
= 5,070249
Pr = 0,022407 Tr Z −β (z +εβ )(Z + σβ)
Literasi Z = 1 Dan setelah literasi ke 4 di hasilkan Z
= 0,902665
V
=
V
= 1864,62 cm3/mol
Z .R.T P
d. Soave/Redlich/Kwong equation Untuk persamaan SRK : σ =1 ε
=0
Ψ
= 0,42748
Ω
= 0,08664
ω
= 0,089
α
= (1+(0,48508+1,5517.ω-0,1561.ω 2)(1-Tr0,5))2
α
= 0,965941
q
=
β
=Ω
Z
= 1+ β−q β
Ψ .α = 5,032823 Ω .Tr Pr = 0,022407 Tr Z −β (z +εβ )(Z + σβ)
Literasi Z = 1 Setelah literasi ke 3 dihasilkan : Z
= 0,903822
V
=
V
= 1867,009 cm3/mol
Z .R.T P
e. Peng/Robinson Equation Untuk persamaan RK : σ
= 2,41421
ε
= -0,41421
Ψ
= 0,45724
Ω
= 0,07779
α
= (1+(0,37464+1,54226.ω-0,2699.ω 2)(1-Tr0,5))2
α
= 0,97467
q
=
β
=Ω
Z
= 1+ β−q β
Ψ .α Ω .Tr
= 6,049815
Pr = 0,020118 Tr Z −β (z +εβ )(Z + σβ)
Literasi Z = 1 Setelah literasi ke 2 dihasilkan : Z
= 0,315212
V
=
V
= 651,1274 cm3/mol
Z .R.T P
3.
Diketahui : R
= 83,14 cm3.bar/mol.K
Untuk persamaan RK : σ
=1
ε
=0
Ψ
= 0,42748
Ω
= 0,08664
Mencari nilai Z liquid dan Vapour Zliquid = 1+ β−q β
Z −β (z +εβ )(Z + σβ)
Zvapour = β +( Z +εβ )(Z + σβ)
1+ β−Z qβ
Ditanya : V liquid & V vapour = ….?
a. Diketahui : α = Tr-0,5 = 1,087 q =
Ψ −3 /2 Tr = 6,332 Ω
β =Ω
Pr = 0,03302 Tr
di dapatkan hasilnya yaitu : Propan e
T (K) 313,15
Tc (K) 369,8
Tr (K) 0,847
P (bar) 13,71
Pc (bar) 42,48
Pr (bar) 0,323
α
Q
β
Zliquid
Vliquid
Zvapour
Vvapour
1,087
6,332
0,03302
0,824
1565,1
0,196
372,53
P (bar) 17,16
Pc (bar) 42,48
Pr (bar) 0,323
b. Diketahui α= Tr-0,5 = 1,070 q=
Ψ −3 /2 Tr = 6,040 Ω
β= Ω
Pr = 0,040 Tr
di dapatkan hasilnya yaitu : Propan e
T (K) 323,15
Tc (K) 369,8
Tr (K) 0,874
α
q
β
Zliquid
Vliquid
Zvapour
Vvapour
1,070
6,040
0,040
0,799
1250,22
0,212
323,3
c. Diketahui : α= Tr-0,5 = 1,067 q=
Ψ −3 /2 Tr = 5,999 Ω
β= Ω
Pr = 0,041 Tr
di dapatkan hasilnya yaitu : nbutane
T (K) 373,15
Tc (K) 425,1
Tr (K) 0,878
P (bar) 15,41
Pc (bar) 36,96
Pr (bar) 0,417
α
q
β
Zliquid
Vliquid
Zvapour
Vvapour
1,067
5,999
0,041
0,795
1599,86
0,215
432,23